Well, I don´t want to give jcl a reason to not implement it, but for now, you can go with something like this, Julz:

Code:
#ifndef shd_voltex_c
#define shd_voltex_c

#include <d3d9.h>

#undef INTERFACE
#define INTERFACE IDirect3DTexture9

DECLARE_INTERFACE_(IDirect3DVolumeTexture9, IDirect3DBaseTexture9)
{
    /*** IUnknown methods ***/
    STDMETHOD(QueryInterface)(THIS_ REFIID riid, void** ppvObj) PURE;
    STDMETHOD_(ULONG,AddRef)(THIS) PURE;
    STDMETHOD_(ULONG,Release)(THIS) PURE;

    /*** IDirect3DBaseTexture9 methods ***/
    STDMETHOD(GetDevice)(THIS_ IDirect3DDevice9** ppDevice) PURE;
    STDMETHOD(SetPrivateData)(THIS_ REFGUID refguid,CONST void* pData,DWORD SizeOfData,DWORD Flags) PURE;
    STDMETHOD(GetPrivateData)(THIS_ REFGUID refguid,void* pData,DWORD* pSizeOfData) PURE;
    STDMETHOD(FreePrivateData)(THIS_ REFGUID refguid) PURE;
    STDMETHOD_(DWORD, SetPriority)(THIS_ DWORD PriorityNew) PURE;
    STDMETHOD_(DWORD, GetPriority)(THIS) PURE;
    STDMETHOD_(void, PreLoad)(THIS) PURE;
    STDMETHOD_(D3DRESOURCETYPE, GetType)(THIS) PURE;
    STDMETHOD_(DWORD, SetLOD)(THIS_ DWORD LODNew) PURE;
    STDMETHOD_(DWORD, GetLOD)(THIS) PURE;
    STDMETHOD_(DWORD, GetLevelCount)(THIS) PURE;
    STDMETHOD(SetAutoGenFilterType)(THIS_ D3DTEXTUREFILTERTYPE FilterType) PURE;
    STDMETHOD_(D3DTEXTUREFILTERTYPE, GetAutoGenFilterType)(THIS) PURE;
    STDMETHOD_(void, GenerateMipSubLevels)(THIS) PURE;
    STDMETHOD(GetLevelDesc)(THIS_ UINT Level,D3DSURFACE_DESC *pDesc) PURE;
    STDMETHOD(GetSurfaceLevel)(THIS_ UINT Level,void** ppSurfaceLevel) PURE;//IDirect3DSurface9
    STDMETHOD(LockRect)(THIS_ UINT Level,D3DLOCKED_RECT* pLockedRect,CONST RECT* pRect,DWORD Flags) PURE;
    STDMETHOD(UnlockRect)(THIS_ UINT Level) PURE;
    STDMETHOD(AddDirtyRect)(THIS_ CONST RECT* pDirtyRect) PURE;
};

MY_DECLARE_INTERFACE(IDirect3DVolumeTexture9)
typedef IDirect3DVolumeTexture9 *LPDIRECT3DVOLUMETEXTURE9;

HRESULT WINAPI
    D3DXCreateVolumeTextureFromFileA(
        LPDIRECT3DDEVICE9         pDevice,
        LPCSTR                    pSrcFile,
        LPDIRECT3DVOLUMETEXTURE9* ppVolumeTexture);

#define D3DXCreateVolumeTextureFromFile D3DXCreateVolumeTextureFromFileA

// Creates a volume texture from the given filename
LPDIRECT3DVOLUMETEXTURE9 shd_voltex_create(STRING *filename)
{
	LPDIRECT3DVOLUMETEXTURE9 temptex;
	HRESULT res = D3DXCreateVolumeTextureFromFile((LPDIRECT3DDEVICE9)pd3ddev, _chr(filename), &temptex);
	if(res != S_OK)
	{
		printf("error: %x", res);
		return NULL;
	}
	return temptex;
}

#endif


That creates the volume texture which then only has to be linked to a shader, like this for example:
Code:
// Material event assigning the texture to the shader
void shd_voltex_set()
{
	LPD3DXEFFECT A7_eff = (LPD3DXEFFECT)render_d3dxeffect;
	if(A7_eff != NULL)
	{
		A7_eff->SetTexture("voltex", (LPDIRECT3DVOLUMETEXTURE9)mtl.skill1); //"voltex" is the textures name within the shader, mtl.skill1 is missused as a pointer to the texture
	}
}

//Usage:
somematerial.event = shd_matevent_colorGrading; 
somematerial.flags |= ENABLE_VIEW; //for a pp effect, probably ENABLE_RENDER when applied to entities
somematerial.skill1 = (var)shd_voltex_create("yourvoltex.dds"); //creation of the volumetexture, returns LPDIRECT3DVOLUMETEXTURE9


I am not sure, but I think that it will automatically be destroyed by, when the engine destroys the directx interface or whatever thingy.

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Shader Tutorial (ger)

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